Which term describes a substance that accepts a proton in a Brønsted-Lowry acid-base reaction?

• A. Bronsted-Lowry base
• B. Arrhenius base
• C. Lewis base
• D. Amphiprotic

Answer: (A)

In Brønsted-Lowry acid–base chemistry, acids donate protons and bases accept them. So the substance that accepts a proton is a Bronsted-Lowry base. Its role is to take on H+, forming its conjugate acid after the transfer. For example, ammonia accepts a proton to become ammonium, illustrating this base behavior.

Arrhenius bases are defined by producing hydroxide ions in water, which is a different framework focused on aqueous solutions. A Lewis base describes someone that donates an electron pair, not specifically a proton transfer. Amphiprotic species can both accept and donate protons, so they aren’t limited to the single action described in the question.